Postobon uses NitroHotfill technology in new Yumbo plant

BY TINO KNOLL, KRONES AG

The Colombian beverage group Postobon S.A. is breaking new ground. It is one of the world's first beverage producers to be using the NitroHotfill process for soft drinks. This process injects nitrogen into the filled bottles shortly before they are capped - a financially interesting alternative to the conventional hotfill concept.

Postobon utilizes this technology at its plant in Yumbo, which was newly erected near the town of Cali. Postobon is part of the Ardila Lulle Group, one of Colombia's largest privately owned companies. The Group possesses more than 80, employing around 40,000 people.

So far, Postobon's strategy had been to work with seven bottling plants in the large conurbations and with up to 25 filling facilities in the town and city centers concerned, each of the latter reflecting the size of the territory being served. The smallest unit produces about 300,000 crates a month, and the largest plant in Bogota three million crates per month. In addition, 55 distribution centers are located all over the country, so as to ensure a sales structure of in-depth efficacy.

Postobon's portfolio includes its own brands Postobon, Colombiana, Bretana, Hipinto, Lux, Frescola, Castalia and Popular, Agua Cristal, Agua Oasis, Hit, Squash and Peak, and also some beverages produced under license, like the aromatized water H2Oh!, Pepsi-Cola, 7up, Gatorade, Lipton and Canada Dry.

New plant on a greenfield site

Postobon accomplished a major step towards modernization of its filling plants and relocating them away from the town/city centers with completion of the newly built facility in Yumbo, a suburb of Cali, which went into operation at the end of 2008. This greenfield facility started off with a new complete line from Krones, rated at 32,000 bph, and used for filling soft drinks in PET containers. A Contiflow here handles beverage blending, with a Volumetic VODM-PET monobloc-synchronized with a Variojet rinser responsible for filling the bottles, while labeling is performed by a Contiroll HS and packing by a Variopac Pro FS tray packer/shrink-wrapper. In 2009, Postobon then relocated the two existing returnable-glass lines from its old plant (subsequently closed down) in the city center of Cali. One of these two lines specializes in large, family-size bottles holding 1.25 l, and the second one in single-serve bottles measuring 250 ml, 350 ml and 500 ml. The latter also handles returnable PET containers and for this uses an Aircontronic contamination detector from Krones.

The fourth line commissioned in May 2010 was the Krones PET line featuring NitroHotfill technology. There are plans for a fifth line to bottle the Agua Cristal table water. But the 18 hectares so far used for the present-day bottling plant only account for half of the entire plot. This facility, with a payroll of 180 in the production operation, already running in three shifts, is definitely amenable to expansion. Also integrated into the plant is the Iberplast company, a subsidiary of Ardila Lulle, which makes PET preforms in Bogota and is in Yumbo responsible for producing the PET containers.

Squashes, juices, ice teas, sports drinks The new NitroHotfill line, rated at 30,000 containers an hour, serves for filling 'Hit' fruit juices and squashes with a fruit juice content of 36-51%, plus fruit-juice beverages containing 8% fruit juice, in a variety of flavors like orange/pineapple, mango, pear or tropical fruit, as well as Mr. Tea ice teas and Squash sports drinks, into 500 ml and 1.5 l PET bottles. To enable Postobon to ensure microbiological safety for filling these sensitive beverages, the firm opted for hot-filling. First of all, the hotfill bottles are produced in a Contiform H18 RC (Relax Cooling) directly linked to a Volumetic filler in a monobloc configuration. What's special about this filler is a function for dosing nitrogen into the filled bottle by means of a droppler that has been integrated into the transfer starwheel between the filler's carousel and the capper. This injection of liquid nitrogen gives the capped bottles an enormous amount of extra stability, thus rendering the use of hotfill containers with special stabilising panels superfluous. And so the 0.5 l container manages with a weight of just 25 g. Subsequently, the full bottles are cooled down to ambient temperature in a LinaCool flow-type cooler, after which the containers' walls are dried before the bottles can be labeled. For this purpose, Postobon has two options: either wrap-around labeling with a Contiroll HS (High Speed) or alternatively sleeving in a Sleevematic Inline followed by a downstream steam tunnel. Option for doing without a panel design In the NitroHotfill process, using a nitrogen injection unit installed shortly before the capper, the bottles are pressurized with 1.5 to 2 bar. Dosing in nitrogen after the filling operation requires ultra-accurate metering. The head-space volume in the bottle, somewhat larger with this process, is filled by the evaporating nitrogen, so that no microbiological disadvantages are entailed. Recooling after bottling would normally cause the product volume to shrink. But this shrinkage is compensated for by the positive bottle pressure created by the nitrogen injected beforehand, thus reliably preventing bottle deformation due to under pressure. The panel design, previously essential for PET containers so as to counteract the vacuum pressure with hot-filled products, is thus rendered superfluous. Doing without the panels means that the bottle dress can be more distinctively matched to the specific marketing concept involved, and the bottle also fits more easily into the hand than a normal hotfill bottle.